I've found out that it just starts playing the 'beeping' noise but doesn't register the bomb.
it happens whenever you drop down on someone and they quickly dash out of your aim, but still within range that it would target them if you were to look at them directly.
Its not a permanent solution but you could all temporarily run a new account and invite that one to play till its fixed, i dont think theres much we can do from a customer side.
Does it happen to try too many times in a row a.k.a you scroll a bunch of trigger points
Or does it happen also when you carefully scroll and dont override the first command?
I've had it multiple times now that im playing bebop and place a bomb on an enemy, followed up by an audible BEEP sometimes even two beeps only to get my bomb refunded and the game pretends like its never been casted.
However the damage i took trying to infiltrate to place those buggers does...